Right, going to shove my 2p in here as I've been doing this on the cheap since I started and I've made some interesting mistakes along the way
😱)
Ignore TPN+ it's really expensive for what it is and James has helpfully calculated the recipe for how to make it. Have a look at it
hereand then have a look in the ferts section to find out where to buy the ingredients.
Mixing Substrates - I used pond soil topped with play sand when I started out, it was good, I wasn't dosing the water column at the time so it helped the few plants I had in there. However it mixed together fairly quickly as things got moved or re-placed (or with the excavations of snails) plus the soil has a limited amount of nutrients in it so doesn't last forever.
I also tried some clay balls like the type you use under orchids to keep the air moist, they looked ideal but floated... so if you're going to try something a bit off the wall then check it meets the basic criteria first - will sink, no perfumes, won't crumple to pieces the moment you put it in water.
Play Sand - This is what I've been using to good effect for the last couple of years, it's fine with a dosed water column and I've a tank with lots of thriving crypts (plants which are more traditionally thought to be 'root feeders' but which we now know get on fine with nutrients coming through the water column).
I have just ordered akadama - mainly on an aesthetic level, I like the idea of a darker substrate with larger particles and if it happens to give a boost by having a high CEC then all the better.
🙂
So generally, if you're trying to keep it cheap then decide what look you want and buy the cheapest option that fits, then dose the water column to suit your CO2 and Lighting conditions. If you feel you need more nutrients at the plants roots then you can always add root tabs, I've bought some but have yet to need them as I find I need to prune often enough as it is
